It is known to provide an inflatable restraint system in a vehicle such as an automotive vehicle to augment protection traditionally afforded vehicle occupants through the use of seat belts. In some automotive vehicles, the inflatable restraint system may be a side air bag system disposed within an occupant compartment in the automotive vehicle in close proximity to either a driver occupant or one or more passenger occupants. Typically, the side air bag system includes a side air bag module attached to a frame of a seat and having an air bag for deployment through an opening in the seat to extend in an occupant compartment of the automotive vehicle. The deployed air bag isolates the occupant from forcefully striking parts on the side of the automotive vehicle as a result of a collision.
It is known to provide an air bag system that provides initial inflated coverage and extended inflated coverage at predetermined locations of the automotive vehicle. An example of such an air bag system is disclosed in co-pending application, U.S. Ser. No. 08/918,833, filed August 1997. This air bag system included an inflator and an air bag cushion having an inflatable transfer portion in fluid communication with the inflator for initial inflation by the inflation gas. The air bag cushion included an inflatable bladder portion in fluid communication with the transfer portion for extended inflation by transfer of inflation gas from the transfer portion. The bladder portion engages the transfer portion to limit the amount of gas further transferred into the bladder portion and to seal the bladder portion such that inflation gas is held in the bladder portion for lengthened and extended inflation of the bladder portion event after deflation of the transfer portion for extended coverage of a pre-selected vehicle location.
Although the above side air bag system has worked well, it is desirable to provide a new side air bag system which removes the internal bladder and retains pressure for extended periods under certain conditions. It is also desirable to provide a side air bag system that is a curtain type head air bag and removes the internal bladder from the air bag to reduce relative complexity, cost and manufacturing operations. Therefore, there is a need in the art to provide an improved side air bag system for an automotive vehicle.